


ISS (International Space Station)

by DaisyFairy



Category: Sherlock (TV)
Genre: Anal Sex, Astronaut AU, First Time, M/M, They are on the Space Station, Tumblr Prompt, Zero-G sex
Language: English
Status: Completed
Published: 2016-08-15
Updated: 2016-08-15
Packaged: 2018-08-09 01:06:16
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,099
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7780993
Author URL: https://archiveofourown.org/users/DaisyFairy/pseuds/DaisyFairy
Summary: <blockquote class="userstuff">
              <p>John and Sherlock are astronauts on the International Space Station. They have been flirting for two weeks, but when John goes on a space walk and Sherlock talks to him over the radio it is time to take their relationship to the next level.</p>
            </blockquote>





	ISS (International Space Station)

**Author's Note:**

  * For [darcylindbergh](https://archiveofourown.org/users/darcylindbergh/gifts), [hudders-and-hiddles (rivndellelf)](https://archiveofourown.org/gifts?recipient=hudders-and-hiddles+%28rivndellelf%29).



> I saw a tumblr prompt about John and Sherlock being on the ISS. I think the post was by Proton-Packs, but I saw it reblogged by Hudders-and-hiddles and Darcylindbergh. Well, then I did the thing.

As systems engineer John Watson of the International Space Station enters the airlock he contemplates his last hour of hell. He has been on a solo space walk to swap out a part on the antenna, trapped in his space suit, sweating with exertion. It is always hard work, the constant control required in the low gravity to carry out the delicate procedure would have taken its toll on its own, but then bloody Sherlock Holmes had hacked into the communications and started talking to him over the radio. 

They've been flirting for two weeks, ever since John arrived at the ISS for what will be his last tour in space. He is there primarily as a systems engineer, with the added benefit of his medical training meaning he is doubling as a medical officer, along with the normal duties of a member of the crew. The shoulder injury that he had sustained in training is still playing up and he doesn't kid himself, if he couldn't pull double duty he is unlikely to have been picked for this, would probably have been forced to retire before getting to go into space again. Sherlock in contrast seems to have managed to get on board the space station purely to carry out his zero-g experiments, and to have completely avoided being put on the rota for any of the house keeping tasks that everyone else shares. 

The second their eyes had met when John had boarded the station he had felt a connection. They have been spending every spare second together ever since. He's not really sure how Sherlock has been surviving up here without him, the man seems to get so caught up in his experiments that he forgets to eat or sleep, just drinking coffee endlessly to keep awake, and John has to nag him to look after himself. He is also neglecting his exercise regime, without it he will lose bone mass and be weak as a kitten when he returns to earth so several times John has literally dragged him to the treadmill. That isn't entirely selfless, John loves to watch him exercise, the flush on Sherlock's face and the sheen of sweat on his skin is absolutely beautiful and he has on several occasions found his mind wandering to other activities that could cause Sherlock to flush like that. To be honest John is completely gone on the tall genius, his mind is brilliant, he can know everything about you at a glance, the others hate it but John thinks it is amazing, the feeling of being so exposed is in equal parts terrifying and exhilarating. 

They haven't labeled what they have, John is fairly sure this connection with another human being is a completely new experience for Sherlock. There has been casual touching, a tap on the shoulder, a hand on the forearm, but up until now Sherlock has seemed shy of any real physical affection, however it seems that he has found some extra courage whilst not being face-to-face. The flirting over the radio had been outrageous, and the number of innuendos regarding John using his big tools and making sure to get the screw into the hole had made John blush, and his heart rate speed up so much that ground control had become concerned and made him stop moving for five minutes. 

Not to mention how uncomfortable it was when his cock tried to harden in the tight confines of his space suit. Then of course there is the embarrassment, Sherlock may have been feeling braver not having to look John in the eye, but as John had reminded him several times all radio communications were monitored by the commanding officer of the ISS (and anyone else who happened to be around when she listened), and the ground crew. In fact from the suggestion that ground control had made as he came into the airlock ("A quick wash might be in order Watson before your debrief, and don't forget, in space, no-one can hear you scream") he would be surprised if they weren't taking bets on how long it would be before they shagged, and were monitoring the cameras for confirmation.

After the air has finished cycling he exits the airlock and meets Susan Calvin, she is one of the other systems engineers, the youngest member of the crew on her first tour in space. She helps him as he takes off the outer suit, no easy task with the stiff fabric and all of the clasps and fastenings. John tries to talk professionally about the space walk but she obviously knows all about the conversation he had with Sherlock over the radio and he has to deflect the conversation several times to avoid talking about it. 

When they have finally finished he mumbles a goodbye and pushes off of the wall gliding to the crew quarters, using the hand holds on the walls and ceilings periodically to control his movements. Sherlock is nowhere to be seen, obviously hiding out in the lab, git. John doesn't want to follow the ground crew's instructions to have a wash, sure that they will be laughing their heads off, but he is drenched in sweat so he peels the form fitted inner suit off and floats into the "shower". 

Rinsing briskly with the hose and soap, then passing the vacuum hose over himself to capture all of the water droplets before he leaves the sealed cubicle John struggles not to touch himself. His erection had never had a chance to fully harden in the space suit, and thankfully has waited until now to make itself known, otherwise poor Susan would have been confronted with it as she helped him to remove the heavy outer suit. Now though, with the things Sherlock had implied, his head is full of such wickedly beautiful images and the temptation is immense. The blood is rushing to his groin causing his penis to thicken and jut straight out from his body, he can feel the tingle of arousal low in his abdomen, his muscles tensing rhythmically, minutely, almost uncontrollably in tiny thrusts, as if they are rehearsing the deeper thrusts that his body is longing for. His lips part with a gasp and a breathy sigh as the image appears in his mind of those deep thrusts being into Sherlock's gorgeous body as the man below him writhes in pleasure. It seems as if every nerve in his body is focused on his cock, his brain is buzzing with the desire for release and he want nothing more than to take himself in hand right now but there are several crew members off shift at the moment, they must be in their sleep cubicles only metres away. 

It isn't as if it never happens, there is no privacy in space, so you occasionally have to ignore the sounds as someone indulges in some personal time in their bunk, but right now, with all the gossip that must be going on he just can't stand the embarrassment that will follow if they hear him. In fact, there is someone out there right now, he can hear them moving around the cabin.

He takes a minute to calm himself, managing to make himself at least passably presentable with the miniscule towel wrapped around his waist. He pulls open the door, planning on making a dash to his bunk and pulling the curtain across but is stopped in his tracks by the sight in front of him.

Sherlock is floating upside down near the ceiling covering the lens of the cabin camera with a sock. He is wearing his normal blue uniform over a white undershirt, and his dark hair floats around his head in a halo. John's breath hitches in surprise, then he whispers "What are you doing?" Mindful of the sleeping men in their bunks.

"No need to be quiet, I have arranged for us to have the cabin to ourselves." He pushes down from the ceiling and twists in mid air so that they are the same way up. He smiles and licks his lips seductively, "Come on John, we both know you want me, what are you waiting for."

John flushes and tries to cover his now burgeoning erection with his hand "Everyone knows what we are doing. Aren't you embarrassed?"

"Embarrassed that Medical Officer John Watson wants me? No."

John wants this, he knows Sherlock wants this, but still he holds back. This is highly likely to leak and then the whole planet will be talking about it, the first gay sex in space, he isn't even officially out. "People will talk, the whole world will talk."

"They do little else. Are you going to let that stop you?" Sherlock slowly lowers the zip on his overall as he says this staring into John's eyes. He pulls his arms free and then yanks his shirt over his head showing miles of pale skin covering his chest and toned stomach, the shirt is discarded and tumbles across the cabin, twisting as it goes. His small pink nipples are hard nubs against the strong pectoral muscles and a sparse trail of dark hair leads down from his navel, disappearing into the grey pants that are peaking out from the lower half of his overalls. As his eyes drop lower John can see the unmistakable bulge, Sherlock's hard length straining against the blue uniform. John's resolve dissolves and he growls low in his throat. 

He pushes away hard from the shower cubicle door behind him, his towel left floating in his wake as he flies through the air naked towards Sherlock. They collide, and with John hitting him off centre the two men float towards the far end of the cabin spinning in a pirouette as they kiss desperately. They crash into the closed cabin door, John hitting his head on one of the metal handholds and cursing in pain. It is not enough to break the kiss, they continue desperately clinging together, lips crushed together and tongues tangling, Sherlock tastes of the overly sweet coffee that he loves, and smells of soap and deodorant underlaid with a hint of the slightly sour smell of sweat that comes from months in space without access to a proper shower. They bounce off of the door and are soon floating in mid air still slowly twirling around one another.

John tries to push Sherlock's clothes down, but with nothing to brace against manages to push himself up towards the ceiling and Sherlock down towards the floor. Sherlock laughs and looking up into John's eyes licks the underside of his penis which has ended up directly in in front of his face.

"Fuck. That's amazing." John cries. He pushes off from the ceiling and snagging Sherlock's arm on the way past uses his momentum to get them both over to the wall. Humming in triumph he holds onto the counter by the wall and braces against it to remove Sherlock's clothing. He then finds himself in prime position to return the favour when Sherlock's erection springs free. Licking the hard length then swirling his tongue around the head and tasting the bitter tang of pre-come.

Sherlock breathlessly cries "Christ John. I didn't know it would be like that."

John pauses and looks up to ask for confirmation "You've never done this before?"

"No. Don't stop. I want you inside me."

"God yes!" John pushes away and moves to his bunk at the opposite side of the cabin. Sherlock is momentarily confused, but then John rummages in his locker and pulls out a tub of vasoline and smiles predatorily at him.

They both push against the wall and crash together in the middle of the room, their momentum being almost equal they come to a stop in mid air and begin kissing again. John coats his fingers in Vaseline and drops the tub leaving it floating next to them. They continue to kiss, Sherlock wrapping his arms around John, desperate to hold him close, as John cups Sherlock's buttocks then moves his lubed fingers slowly towards his hole. He gently circles the furled muscle which tenses at the unfamiliar sensation until he feels Sherlock relax, then slowly pushes his finger inside. Sherlock needs to stop kissing as he pants, throwing his head back overwhelmed by the feeling of this first intrusion into his body. John takes advantage of this to kiss and suck on the long column of his neck, distracting Sherlock as he inserts a second finger. Sherlock feels a slight burn with the stretch, but kissing and being held by the man he has trusted with his body allows him to relax until the burn is gone and he is left with a pleasant fullness.

Several minutes later they are both panting and gasping as John pumps three fingers in and out of Sherlock. He twists them just right and finds the small bundle of nerves inside, drawing a sob from his lover. "Ready?" He whispers, and Sherlock can only nod in response.

They work together to twist Sherlock in John's arms, he almost folds himself in half, bending over and grasping his thighs. John takes a second to admire the beautiful sight of the naked man floating in the mid air, presenting his slick hole shamelessly for him. John slashers his penis quickly in lube and moves into position behind him, lines himself up and tries to push the flushed head of his cock inside Sherlock, but he does not have a firm enough grip on his hips and the effort causes them to begin floating apart. He grabs Sherlock's hips hard, digging his fingertips into the firm flesh and leaving half moon imprints of his nails, to get leverage and pushes through the tight ring of muscle, both men breathing hard through the sensation. 

He moves slowly at first, long deep thrusts that cause Sherlock to gasp when he has taken all of John's length. Both men are drenched in sweat, beads of it floating around them in a cloud, John can taste them, the salty fluid of their combined effort finding it's way to his tongue as he breathes open mouthed. John leans over and kisses Sherlock's back, then pulls out "We need leverage to do this right." He whispers, then begins swimming towards the wall. 

Sherlock follows him and holds tight to two of the handholds and hooks his feet into two handholds on the floor. John grabs Sherlock's shoulders and hooks his feet around Sherlock's calves, then pushes in hard, returning to the tight heat is such a relief he nearly comes immediately, but manages to control himself and pull out then snap his hips forward again.

"Harder John. Please." Sherlock cries brokenly.

Never one to shirk from a challenge John begins thrusting as fast and hard as he can, he finds the angle to brush against Sherlock's prostate making him moan louder with every thrust. John moves one of his hands around to stroke Sherlock, he can feel a cloud of precome floating around the end of his cock and coats his hand in it to ease the glide. He only manages a few strokes from root to tip before Sherlock is coming, almost screaming with his release and come shooting against the wall. The clench of his muscles around him draws John's own orgasm out he grunts through it, his muscles tensing and pulling him closer to Sherlock, buried to the hilt inside of him.

They stay like that for several seconds muscles locked in place, then they both relax, Sherlock releasing his grip on the wall, but his feet remain hooked onto the floor. John goes lax and lets go of Sherlock, the force of his movements setting him to slowly drift away, until the movement stops, arrested by John still being tethered inside Sherlock.

John's eyes had slammed closed during his orgasm, he reopens them and then reaches down to snuggle into the man below him. Kissing Sherlock's back gently he asks "Was that ok? How you imagined it?"

A dreamy voice answers "Yes, perfect. So much better than I imagined."

John looks around and can see a cloud of sweat droplets slowly spreading across the room. The towel he had dropped and all of Sherlock's clothes are scattered around the cabin, and looking down he can see blobs of a white viscous fluid floating away from them. Dammit they are going to have to clean all this liquid up before it gets into the circuitry.

He pulls out gently, but even so Sherlock winces a little, a few more droplets of white fluid escape into the air, leaking out of Sherlock's hole and John suddenly feels unaccountably possessive at the thought that he has filled this man up with his seed. He just wants to hold him, but they are going to be in enough trouble for Sherlock hijacking the radio without having to explain to an investigative committee why a control panel has short circuited due to semen in the works.

He recovers the towel and then floats around the cabin absorbing the fluid, then wiping down the wall where they had attached themselves.

"I'm still cross with you you know. This was entirely inappropriate."

"Hmmm." Is the only reply Sherlock seems capable of, an expression of pure happiness shaping his features.

"Come on then genius, why did it have to be like this? We could have just snuck into my bunk one day when no one was around and if we were lucky no one would ever have known."

Sherlock's eyes sharpen as he lifts his head. "But I wanted them to know, I don't want this to be a dirty secret. No one has wanted me before, not once they actually got to know me, and I wanted to show everyone that I am yours. I love you John Watson."

John smirks and says fondly "Idiot. People normally keep the sex thing quiet, they save the showing the world they are together thing for the wedding. Oh, and, yeah, I love you too."

"Wedding?"

"One step at a time, yeah? Now we need to get cleaned up and I need to go to my debriefing, Christ ground control must have been waiting for me."

With a giggle Sherlock says "I thought I just gave you your debriefing." Then launches himself across the cabin and captures John in his arms, kissing him thoroughly as the pair tumble slowly across the room, smothering any protests before John can give them voice.

**Author's Note:**

> As you may have guessed, I am not an astronaut so all details in this come from watching Sci-fi films, any inaccuracies I blame on Hollywood ;-)
> 
> I am DaisyFairy1 on Tumblr.


End file.
